The current status of primary prevention in coronary heart disease

During the second part of the twentieth century, research advances caused a substantial decline in the rate of coronary heart disease. The decline lasted from the mid-1960s until the early 1990s and occurred primarily in Western countries. However, an unfavourable trend in coronary heart disease related mortality has gradually developed during the 1990s, with cardiovascular diseases anticipated to remain the main cause of overall mortality for the foreseeable future. The present paper aims at analyzing the current status of the main determinants of population-wide coronary heart disease prevention

Effect of Omacor on HRV parameters in patients with recent uncomplicated myocardial infarction – A randomized, parallel group, double-blind, placebo-controlled trial: study design [ISRCTN75358739]

BACKGROUND: A large body of data derived from animal, epidemiological and clinical studies indicate that n-3 polyunsaturated fatty acids have a favourable effect on the prognosis of patients with cardiovascular disease in general, and on reducing sudden death in particular. Depressed heart rate variability (HRV), an indicator of impairment of the autonomic nervous system, has been shown to be a powerful predictor of subsequent mortality in patients surviving an acute myocardial infarction. A multitude of studies have demonstrated this strong association, suggesting that the imbalance in the sympathic/parasympathetic system may facilitate emergence of ventricular arrhythmias. Heart rate variability parameters will be assessed in the present study, with the primary objective of evaluating the possible superiority of Omacor (a highly refined, concentrated omega-3 fatty acid) versus placebo in improving HRV from baseline to endpoint in patients with recent uncomplicated myocardial infarction. Both groups will receive optimal conventional treatment. The study will also explore and quantify improvement in time domain HRV indices and will assess the safety of administering Omacor to optimally treated post-infarction patients (conventional treatment). METHODS: This multi-centre study will evaluate the effect of Omacor 1 g, o.d. on time-domain HRV parameters in comparison to placebo o.d. in patients with recent uncomplicated transmural myocardial infarction. Patients will be screened during the first few days after the acute event as appropriate for the patient's condition, and after obtaining informed consent. Based on inclusion/exclusion criteria, a first 24-hour Holter recording will be performed. Two to five days later, screened patients still eligible for the study will undergo a second 24-hour Holter recording. After the second Holter recording, all patients will be randomly allocated to treatment with Omacor 1 g, o.d. or placebo o.d. One hundred patients will be followed in double-blind fashion for a six-month period after randomization. Visits, including 24-hour Holter recording and assessment of adverse events, will take place at one-month intervals ± five days after randomization, i.e., six times in all

Design of a randomized controlled trial of comprehensive rehabilitation in patients with myocardial infarction, stabilized acute coronary syndrome, percutaneous transluminal coronary angioplasty or coronary artery bypass grafting: Akershus Comprehensive Cardiac Rehabilitation Trial (the CORE Study)

OBJECTIVES: 1. To assess the long-term effectiveness of a comprehensive cardiac rehabilitation programme on quality of life and survival in patients with a large spectrum of cardiovascular diseases (myocardial infarction, acute coronary syndrome, percutaneous transluminal coronary angioplasty and coronary artery bypass grafting). 2. To establish the degree of correlation between expected improvement of health-related quality of life and improvement in physical function attributable to rehabilitation in the intervention group, in comparison with similar changes in the conventional care group. DESIGN: Randomized, controlled, parallel-group design (intervention/conventional care). SETTING: Akershus County, southeast of Oslo City, Norway. PARTICIPANTS: 500 patients, men and women, aged 40-85 years, who have sustained at least one of the above-mentioned cardiovascular diseases. INTERVENTIONS: 8 weeks of supervised, structured physical training of three periods of 20 min per week, targeting a heart rate of 60-70% of the individual's maximum; home-based physical exercise training with the same basic schedule as in the supervised period; quantification of patients' compliance with the exercise programme by the use of wristwatches, information stored in the watch memory being retrieved once a month during the 3-year follow-up period; and life-style modification with an emphasis on the cessation of smoking and on healthy nutrition and weight control

Current trends in the cardiovascular clinical trial arena (I)

The existence of effective therapies for most cardiovascular disease states, coupled with increased requirements that potential benefits of new drugs be evaluated on clinical rather than surrogate endpoints, makes it increasingly difficult to substantiate any incremental improvements in efficacy that these new drugs might offer. Compounding the problem is the highly controversial issue of comparing new agents with placebos rather than active pharmaceuticals in drug efficacy trials. Despite the recent consensus that placebos may be used ethically in well-defined, justifiable circumstances, the problem persists, in part because of increased scrutiny by ethics committees but also because of considerable lingering disagreement regarding the propriety and scientific value of placebo-controlled trials (and trials of antihypertensive drugs in particular). The disagreement also substantially affects the most viable alternative to placebo-controlled trials: actively controlled equivalence/noninferiority trials. To a great extent, this situation was prompted by numerous previous trials of this type that were marked by fundamental methodological flaws and consequent false claims, inconsistencies, and potential harm to patients. As the development and use of generic drugs continue to escalate, along with concurrent pressure to control medical costs by substituting less-expensive therapies for established ones, any claim that a new drug, intervention, or therapy is "equivalent" to another should not be accepted without close scrutiny. Adherence to proper methods in conducting studies of equivalence will help investigators to avoid false claims and inconsistencies. These matters will be addressed in the third article of this three-part series

Equivalence and noninferiority trials – are they viable alternatives for registration of new drugs? (III)

The scientific community's reliance on active-controlled trials is steadily increasing, as widespread agreement emerges concerning the role of these trials as viable alternatives to placebo trials. These trials present substantial challenges with regard to design and interpretation as their complexity increases, and the potential need for larger sample sizes impacts the cost and time variables of the drug development process. The potential efficacy and safety benefits derived from these trials may never be demonstrated by other methods. Active-controlled trials can develop valuable data to inform both prescribers and patients about the dose- and time-dependent actions of any new drug and can contribute to the management and communication of risks associated with the relevant therapeutic products

The Blood Pressure "Uncertainty Range" – a pragmatic approach to overcome current diagnostic uncertainties (II)

A tremendous amount of scientific evidence regarding the physiology and physiopathology of high blood pressure combined with a sophisticated therapeutic arsenal is at the disposal of the medical community to counteract the overall public health burden of hypertension. Ample evidence has also been gathered from a multitude of large-scale randomized trials indicating the beneficial effects of current treatment strategies in terms of reduced hypertension-related morbidity and mortality. In spite of these impressive advances and, deeply disappointingly from a public health perspective, the real picture of hypertension management is overshadowed by widespread diagnostic inaccuracies (underdiagnosis, overdiagnosis) as well as by treatment failures generated by undertreatment, overtreatment, and misuse of medications. The scientific, medical and patient communities as well as decision-makers worldwide are striving for greatest possible health gains from available resources. A seemingly well-crystallised reasoning is that comprehensive strategic approaches must not only target hypertension as a pathological entity, but rather, take into account the wider environment in which hypertension is a major risk factor for cardiovascular disease carrying a great deal of our inheritance, and its interplay in the constellation of other, well-known, modifiable risk factors, i.e., attention is to be switched from one's "blood pressure level" to one's absolute cardiovascular risk and its determinants. Likewise, a risk/benefit assessment in each individual case is required in order to achieve best possible results. Nevertheless, it is of paramount importance to insure generalizability of ABPM use in clinical practice with the aim of improving the accuracy of a first diagnosis for both individual treatment and clinical research purposes. Widespread adoption of the method requires quick adjustment of current guidelines, development of appropriate technology infrastructure and training of staff (i.e., education, decision support, and information systems for practitioners and patients). Progress can be achieved in a few years, or in the next 25 years

Beyond the Evidence of the New Hypertension Guidelines. Blood pressure measurement – is it good enough for accurate diagnosis of hypertension? Time might be in, for a paradigm shift (I)

Despite widespread availability of a large body of evidence in the area of hypertension, the translation of that evidence into viable recommendations aimed at improving the quality of health care is very difficult, sometimes to the point of questionable acceptability and overall credibility of the guidelines advocating those recommendations. The scientific community world-wide and especially professionals interested in the topic of hypertension are witnessing currently an unprecedented debate over the issue of appropriateness of using different drugs/drug classes for the treatment of hypertension. An endless supply of recent and less recent "drug-news", some in support of, others against the current guidelines, justifying the use of selected types of drug treatment or criticising other, are coming out in the scientific literature on an almost weekly basis. The latest of such debate (at the time of writing this paper) pertains the safety profile of ARBs vs ACE inhibitors. To great extent, the factual situation has been fuelled by the new hypertension guidelines (different for USA, Europe, New Zeeland and UK) through, apparently small inconsistencies and conflicting messages, that might have generated substantial and perpetuating confusion among both prescribing physicians and their patients, regardless of their country of origin. The overwhelming message conveyed by most guidelines and opinion leaders is the widespread use of diuretics as first-line agents in all patients with blood pressure above a certain cut-off level and the increasingly aggressive approach towards diagnosis and treatment of hypertension. This, apparently well-justified, logical and easily comprehensible message is unfortunately miss-obeyed by most physicians, on both parts of the Atlantic. Amazingly, the message assumes a universal simplicity of both diagnosis and treatment of hypertension, while ignoring several hypertension-specific variables, commonly known to have high level of complexity, such as: - accuracy of recorded blood pressure and the great inter-observer variability, - diversity in the competency and training of diagnosing physician, - individual patient/disease profile with highly subjective preferences, - difficulty in reaching consensus among opinion leaders, - pharmaceutical industry's influence, and, nonetheless, - the large variability in the efficacy and safety of the antihypertensive drugs. The present 2-series article attempts to identify and review possible causes that might have, at least in part, generated the current healthcare anachronism (I); to highlight the current trend to account for the uncertainties related to the fixed blood pressure cut-off point and the possible solutions to improve accuracy of diagnosis and treatment of hypertension (II)